Class Code 8397
Auto Or Truck Transmission Repairing And Rebuilding
Class Code 8397 applies to businesses that perform auto or truck transmission repairing and rebuilding, including disassembly, machining, reassembly and bench or road testing. The approved pure premium rate for California effective September 1, 2026 is $4.817 per $100 of payroll, a key factor in workers' comp cost for these shops.
What Class Code 8397 Covers
This classification covers work specifically devoted to the repairing, rebuilding and remanufacturing of automotive and truck transmissions and related components such as torque converters, clutches, input/output shafts, planetary gear sets and valve bodies. It includes removing transmissions from vehicles, bench disassembly and inspection, machining or replacing worn gears and bearings, press-fitting and welding operations, replacement of seals and bearings, reassembly, fluid services, and both bench and road/dyno testing. Also included are ancillary tasks integral to the transmission job: diagnosing transmission faults, testing solenoids and electronic controls, and handling transmission fluids and cleaning solvents. Jobs involving only minor adjustments or parts replacement that do not involve rebuilding typically belong to different automotive codes; full rebuild shops and remanufacturers belong here.
Who It Applies To
- Independent transmission rebuilding and remanufacturing shops
- Auto repair shops that perform complete transmission overhauls
- Commercial truck fleet maintenance shops that rebuild transmissions in-house
- Mobile transmission repair services that perform on-site removals and rebuilds
- Remanufacturers and specialty shops rebuilding torque converters and valve bodies
Common Job Duties
- Removing and reinstalling transmissions from cars, light trucks, and commercial vehicles
- Disassembling and inspecting gear sets, bearings, and seals
- Machining, reconditioning, or replacing gears, shafts, and housings on lathes or mills
- Press-fitting components, welding, and using hydraulic presses
- Bench assembly, use of test stands or dynos, and road testing rebuilt units
- Handling, storing, and disposing of transmission fluids and cleaning solvents
Common Injury Risks
Understanding the $4.817 Rate
The pure premium rate of $4.817 per $100 of payroll represents the WCIRB's estimate of expected claim costs for the class before insurer adjustments. Insurers apply this rate to your payroll, then add expense loads, schedule ratings, and the employer's experience modification to calculate the final premium. Final cost is affected by payroll size and mix, loss history, deductible choices, and safety or return-to-work programs.
Cal/OSHA Compliance Requirements
Transmission rebuilding shops must follow Cal/OSHA requirements including a written Injury and Illness Prevention Program (IIPP), Hazard Communication for solvents and fluids, machine guarding, and control of hazardous energy (lockout/tagout) during removal and repairs. Employers should implement adequate ventilation for solvent use, provide PPE (gloves, eye protection, hearing protection), train workers on safe use of presses and hoists, and maintain equipment inspection records to meet Cal/OSHA expectations.
How Key HR Helps Employers Under Class Code 8397
A PEO like Key HR helps transmission shops manage workers' comp costs through accurate payroll classification and reporting, proactive loss-control consulting (ergonomics, lifting equipment, machine guarding), and centralized claims management to speed medical care and return-to-work. Key HR can also provide standardized safety training, regulatory compliance support, and data to help lower an employer's experience modifier over time.
Get a QuoteFrequently Asked Questions
How do I know if my shop should be coded to 8397 or a different automotive class?
Use 8397 when employees regularly perform full transmission disassembly, machining, rebuilding and bench/road testing. If your shop only performs minor transmission repairs, fluid changes, or electronic diagnostics without rebuilding, a different automotive class may apply. Keep detailed payroll and job task records; insurers and WCIRB audits look at the actual work performed.
What practical steps reduce claims and premium for transmission rebuilders?
Implement mechanical lifting aids and hoists to reduce manual lifting, maintain and guard presses, enforce lockout/tagout during removal and disassembly, control solvent exposures with ventilation and proper PPE, run training on safe machine operation, and establish a formal return-to-work program to reduce claim costs and frequency.
Can safety programs or my loss history change what I pay for workers' comp?
Yes. A good safety program, documented training, and fewer or lower-severity claims improve your experience modification and can lead to lower premiums. Insurers also offer schedule rating plans and deductible options; working with a PEO or broker can help align these tools with your risk profile.
Quick Facts
- Class Code
- 8397
- Classification
- Auto Or Truck Transmission Repairing And Rebuilding
- Pure Premium Rate
- $4.817 / $100 payroll
- Effective Date
- September 1, 2026
- Source
- WCIRB Approved Filing
Manage Workers' Comp Through a PEO
Key HR provides pay-as-you-go workers' comp for California employers — no large deposits, no audits, better rates.
Get a Quoteor call (800) 922-4133Ready to Simplify Workers' Comp for Class Code 8397?
Key HR provides California employers with pay-as-you-go workers' comp, HR compliance support, and payroll — all through one PEO partnership.